This invention relates generally to improved control means for use on flexible fluid carrying hoses, and more particularly to a novel clamping means whereby both opening and closing of said clamping means can be more effectively controlled during hose operation.
The development and use of various clamping devices to control fluid flow in flexible hoses particularly adapted for use in the fire fighting industry is known. It is often desirable to restrict fluid flow in fire hoses that have been inflated with fluid during the course of fighting a fire. For example, in U.S. Pat. No. 4,978,100 there is disclosed a screw-operated hose clamp designed to completely cut off water flow even when relatively high water pressures, e.g. 250 psi dynamic pressure, are present. The clamp means disclosed therein is in the form of a U-shaped guide structure that completely surrounds the outer surface of the subject hose portion even when the clamp pressure has been released. The clamp means is separated from the hose by unhinging the leg of the U-shaped guide structure to which a stationary jaw is attached. Opening this hinged leg opens a pathway for removal or insertion of a hose.
Temporarily cutting off the fluid flow by engaging a clamp enables the hose sections on the fluid supply side of the clamp to remain filled with fluid. The discharge nozzle at the exit end of the subject hose section can then be disengaged, an additional length of hose can be added, the discharge nozzle can be re-engaged at the exit end of the new hose section, and the hose system quickly recharged by disengaging the clamp.
In another U.S. Pat. No. 4,582,292 there is disclosed a different kind of clamp for use on flexible fire hoses for the purpose of restricting fluid flow therein, whereby the jaws of the clamp are actuated by means of a lever. This prior art clamp features beveled and grooved jaws said to reduce the problem of the hose popping out of the clamp when the clamp is opened. A series of grooves within the lower jaw face that contacts the hose is said to channel the initial surge of fluid generally through the center of the hose upon releasing the clamp, thereby reducing the chance of the hose popping out from between the jaws. Moreover, a flared configuration on the upper jaw face that contacts the hose is said to maintain the hose wedged between the jaws until the jaws are fully opened and normal water flow through the hose is reestablished.
Operation of a flexible hose system in the above described manner occasions clamp movement both upon opening and closing of the particular clamping device being employed. Such clamping device experiences forward movement from the high pressure supply side of the hose toward its lower pressure discharge side at these times. Such movement of the clamp device along the hose can be quite rapid and prevents proper operation of the clamp device. It becomes desirable, therefore, to reduce all such movement when the flow-restricting clamp means are being employed and to do so in a simple and cost effective manner.
It is therefore an object of the present invention to provide a means retarding further movement of said flow restricting type clamping means when being operated with a flexible hose.
It is a still further object of the present invention is to provide frictional engagement means for use in combination with flow-restricting type clamping devices and thereby more effectively regulate clamp operation with a flexible hose.
Still another important object of the present invention is to provide a novel method for operation of a flexible hose with flow-restricting type clamping means.
These and other objects as well as advantages of the present invention will become more apparent from the following description being provided upon the preferred embodiments.